Motion-compensated cardiac MRI using low-rank diffeomorphic flow (DMoCo)
Journal:
arXiv
Published Date:
May 6, 2025
Abstract
We introduce an unsupervised motion-compensated image reconstruction
algorithm for free-breathing and ungated 3D cardiac magnetic resonance imaging
(MRI). We express the image volume corresponding to each specific motion phase
as the deformation of a single static image template. The main contribution of
the work is the low-rank model for the compact joint representation of the
family of diffeomorphisms, parameterized by the motion phases. The
diffeomorphism at a specific motion phase is obtained by integrating a
parametric velocity field along a path connecting the reference template phase
to the motion phase. The velocity field at different phases is represented
using a low-rank model. The static template and the low-rank motion model
parameters are learned directly from the k-space data in an unsupervised
fashion. The more constrained motion model is observed to offer improved
recovery compared to current motion-resolved and motion-compensated algorithms
for free-breathing 3D cine MRI.
